CN111436910A - Optical coherence tomography multi-modal imaging device and method for living tissue - Google Patents

Abstract

The present invention provides an optical coherence tomography multimodal imaging device and method for living tissue, after obtaining the first complex signal sequence group before the acoustic radiation force acts on all the detection positions of the living tissue and after the acting After the second complex signal sequence group; construct the structure image of the living tissue, the elasticity image of the living tissue and the living body according to the first complex signal sequence group and/or the second complex signal sequence group corresponding to all the detection positions Multiple image combinations in tissue blood flow images. It can be seen that the optical coherence tomography multimodal imaging method provided by the present invention can construct various image combinations in the structure image, elasticity image and blood flow image of living tissue, and can simultaneously measure the structure, elasticity distribution and blood flow distribution of living tissue. information to improve the accuracy of disease diagnosis in living tissue.

Description

Optical coherence tomography multimodal imaging device and method for living tissue

technical field

The invention relates to the technical field of medical devices, and more particularly, to an optical coherence tomography multimodal imaging device and method for living tissue.

Background technique

The differences in the elastic mechanical properties of biological tissues are derived from the differences in composition, structure and interaction at the level of biomolecules, cells and tissues. The elasticity measurement of biological tissues is of great significance for evaluating the physiological functions of tissues, and can be used for eyeball, cardiovascular, breast , liver and other parts of the disease diagnosis. Blood flow plays an important role in maintaining the normal physiological function of the body. The distribution of blood flow can indicate the state of biological tissues. Angiography can be used for the diagnosis of tumors, abnormal blood vessels, and the study of brain function. The structure of biological tissue can directly reflect whether the biological structure is abnormal or not. There is an urgent need for a multimodal imaging technology that simultaneously acquires structural images, elastic images and blood flow images of biological tissues, so as to facilitate accurate diagnosis of biological tissue diseases.

SUMMARY OF THE INVENTION

In view of this, the present invention provides an optical coherence tomography (OCT) multimodal imaging device and method for living tissue, which effectively solves the technical problems existing in the prior art and improves the diagnosis of diseases in living tissue accuracy.

For achieving the above object, the technical scheme provided by the invention is as follows:

An optical coherence tomography multimodal imaging method for living tissue, comprising the steps of:

S1. Divide weakly coherent beams of different wavelengths in a predetermined band into a reference beam and a detection beam, control the detection beam to irradiate the detection position on the surface of the living tissue to generate a feedback beam, and control the reference beam to irradiate the mirror to generate a reflected beam , and control the interference of the feedback beam and the reflected beam to generate an interference beam, extract the corresponding interference signal sequence that changes with the wavelength in the interference beam, and perform Fourier transform to obtain the first complex signal sequence of the detection position that changes with depth , so as to obtain a first complex signal sequence group including a plurality of first complex signal sequences corresponding to a plurality of time points that change with depth;

S2. Generate an acoustic radiation force to act on the fixed receiving position of the living tissue, and obtain the detection position according to the method of step S1. After the acoustic radiation force acts, it includes a plurality of second time points corresponding to changes with depth. a second complex sequence group of complex signal sequences;

S3. Repeat the steps S1 and S2 until the scanning of all the detection positions of the detection beam on the surface of the living tissue is completed, and obtain all the first complex numbers of all the detection positions of the living tissue before the action of the acoustic radiation force a set of signal sequences and all second complex signal sequence sets after action;

S4. Construct the structural image of the living tissue, the elasticity image of the living tissue, and the blood flow image of the living tissue according to the first complex signal sequence group and/or the second complex signal sequence group corresponding to all the detection positions Various image combinations.

Correspondingly, the present invention also provides an optical coherence tomography multimodal imaging device for living tissue, comprising: an optical coherence tomography imaging unit and an acoustic radiation force excitation unit;

The acoustic radiation force excitation unit is used to generate a fixed receiving position where the acoustic radiation force acts on the living tissue;

The optical coherence tomography unit is used to divide weakly coherent beams of different wavelengths in a predetermined band into a reference beam and a probe beam before the acoustic radiation force acts on the fixed receiving position of the living tissue, and controls the probe beam to irradiate the probe beam to the The detection position on the surface of the living tissue generates a feedback beam, the reference beam is controlled to be irradiated to the mirror to generate a reflected beam, and the feedback beam and the reflected beam are controlled to interfere to generate an interference beam, and the corresponding wavelength-changing beam in the interference beam is extracted. Interfering with the signal sequence, and performing Fourier transform to obtain the first complex signal sequence in which the detection position changes with depth, so as to obtain a first complex signal sequence group including a plurality of first complex signal sequences corresponding to a plurality of time points that change with depth ; and after the acoustic radiation force acts on the fixed receiving position of the living tissue, obtain a set of detection positions in the above-mentioned manner. After the acoustic radiation force acts, a plurality of second complex signal sequences corresponding to a plurality of time points that change with depth are obtained. The second complex sequence group of The complex signal sequence group and all the second complex signal sequence groups after the action; according to the first complex signal sequence group and/or and the second complex signal sequence group corresponding to all detection positions, construct the structural image of the living tissue, the A plurality of images are combined in the elasticity image of the living tissue and the blood flow image of the living tissue.

Compared with the prior art, the technical solution provided by the present invention has at least the following advantages:

The present invention provides an optical coherence tomography multimodal imaging method for living tissue, comprising the steps of: S1. Divide weakly coherent beams of different wavelengths in a predetermined band into a reference beam and a probe beam, and control the probe beam to irradiate the probe beam to the probe beam. The detection position on the surface of the living tissue generates a feedback beam, the reference beam is controlled to be irradiated to the mirror to generate a reflected beam, and the feedback beam and the reflected beam are controlled to interfere to generate an interference beam, and the corresponding wavelength-changing beam in the interference beam is extracted. Interfering with the signal sequence, and performing Fourier transform to obtain the first complex signal sequence in which the detection position changes with depth, so as to obtain a first complex signal sequence group including a plurality of first complex signal sequences corresponding to a plurality of time points that change with depth S2, generate sound radiation force to act on the fixed receiving position of the living tissue, and obtain the detection position according to step S1. After the sound radiation force acts, it includes a plurality of time points corresponding to a plurality of time points that change with depth. A second complex sequence group of two complex signal sequences; S3, repeating steps S1 and S2 until the scanning of all detection positions of the detection beam on the surface of the living tissue is completed, and obtaining all detection positions of the living tissue at all detection positions Describe all first complex signal sequence groups before the action of the acoustic radiation force and all second complex signal sequence groups after the action; S4, according to the corresponding first complex signal sequence groups and/or second complex signal sequence groups of all detection positions, A plurality of image combinations among the structural image of the living tissue, the elasticity image of the living tissue, and the blood flow image of the living tissue are constructed. It can be seen that the optical coherence tomography multimodal imaging method provided by the present invention can construct various image combinations in the structure image, elasticity image and blood flow image of the living tissue, and then can simultaneously measure the corresponding information of the structure, elasticity and blood flow distribution of the living tissue , to improve the accuracy of disease diagnosis of living tissue.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to the provided drawings without creative work.

1 is a flowchart of a method for optical coherence tomography multimodal imaging of living tissue provided by an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an optical coherence tomography multimodal imaging device for living tissue according to an embodiment of the present invention;

3 is a schematic structural diagram of another optical coherence tomography multimodal imaging device for living tissue provided by an embodiment of the present invention;

4 is a schematic structural diagram of another optical coherence tomography multimodal imaging device for living tissue provided by an embodiment of the present invention;

5 is a schematic structural diagram of a probe beam and living tissue provided by an embodiment of the present invention;

FIG. 6 is a schematic diagram of transformation of an interference signal sequence and a complex signal sequence provided by an embodiment of the present invention;

7 is a schematic structural diagram of different scanning modes for structural imaging according to an embodiment of the present invention;

FIG. 8 is a blood flow image before the action of acoustic radiation force and a projection diagram thereof according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of acquisition of four-dimensional (x, y, z, t) signals and construction of a vibration image after an acoustic radiation force acts according to an embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

As mentioned in the background art, the differences in the elastic mechanical properties of biological tissues are derived from the differences in composition, structure and interaction at the level of biomolecules, cells and tissues. The elasticity measurement of biological tissues is of great significance for evaluating the physiological functions of tissues and can be used Diagnosis of eye, cardiovascular, breast, liver and other diseases. Blood flow plays an important role in maintaining the normal physiological function of the body. The distribution of blood flow can indicate the state of biological tissues. Angiography can be used for the diagnosis of tumors, abnormal blood vessels, and the study of brain function. The structure of biological tissue can directly reflect whether the biological structure is abnormal or not. There is an urgent need for a multimodal imaging technology that simultaneously acquires structural images, elastic images and blood flow images of biological tissues, so as to facilitate accurate diagnosis of biological tissue diseases.

For example, the current diagnosis of fundus diseases mainly relies on the imaging of fundus structures and blood vessels. For age-related macular degeneration (AMD), the clinical diagnosis of age-related macular degeneration is mainly based on fundus blood vessels. Contrast imaging, including fluorescein fundus angiography (Fundusfluorescein angiography, FFA), choroidal indocyanine green angiography (Indocyanine greenangiography, ICGA) and optical coherence tomography (Optical coherence tomography, OCT). During FFA angiography, fluorescein sodium solution is injected intravenously, and then the fundus blood vessel image is taken by the fundus camera to observe the abnormal structure of the fundus blood vessel. However, since the choroidal vessels are blocked by the retinal pigment epithelium layer, it is difficult to clearly image the choroidal vessels with FFA. In order to achieve clearer choroidal angiography, ICGA technology has been gradually developed. ICGA uses indocyanine green (ICG) as a dye, uses near-infrared light as an excitation light source, and records blood flow images in choroidal blood vessels through a near-infrared fundus camera or a laser scanning ophthalmoscope. Both FFA and ICGA are invasive procedures, and there is a certain risk of infection and allergy, and contrast medium allergy and renal insufficiency are contraindications to FFA and ICGA. Therefore, there is an urgent need for a non-invasive, label-free, high-resolution 3D medical imaging technology, and a multimodal imaging technology that simultaneously acquires structural images, elastic images and blood flow images of living tissue, which is convenient for accurate diagnosis of biological tissue diseases.

Based on this, the present invention provides an optical coherence tomography multimodal imaging device and method for living tissue, which effectively solves the technical problems existing in the prior art and improves the accuracy of disease diagnosis on living tissue.

In order to achieve the above purpose, the technical solutions provided by the present invention are as follows, and the technical solutions provided by the embodiments of the present invention are described in detail with reference to FIG. 1 to FIG. 9 .

Referring to FIG. 1, a flowchart of a method for optical coherence tomography multimodal imaging of living tissue provided by an embodiment of the present invention includes steps:

S1. Divide weakly coherent beams of different wavelengths in a predetermined band into a reference beam and a detection beam, control the detection beam to irradiate the detection position on the surface of the living tissue to generate a feedback beam, and control the reference beam to irradiate the mirror to generate a reflected beam , and control the interference of the feedback beam and the reflected beam to generate an interference beam, extract the corresponding interference signal sequence that changes with the wavelength in the interference beam, and perform Fourier transform to obtain the first complex signal sequence of the detection position that changes with depth , so as to obtain a first complex signal sequence group including a plurality of first complex signal sequences corresponding to a plurality of time points that change with depth.

S2. Generate an acoustic radiation force to act on the fixed receiving position of the living tissue, and obtain the detection position according to the method of step S1. After the acoustic radiation force acts, it includes a plurality of second time points corresponding to changes with depth. A second complex sequence group of complex signal sequences. S3. Repeat the steps S1 and S2 until the scanning of all the detection positions of the detection beam on the surface of the living tissue is completed, and obtain all the first complex numbers of all the detection positions of the living tissue before the action of the acoustic radiation force The signal sequence group and all second complex signal sequence groups after action. Wherein, a detection position corresponds to a first complex signal sequence group, and a detection position corresponds to a second complex signal sequence group. And, in a first complex signal sequence group, time points correspond one-to-one with the first complex signal sequence; and in a second complex signal sequence group, time points correspond one-to-one with the second complex signal sequence. It can be understood that each value in a complex signal sequence represents a complex signal of a certain depth, and a complex signal sequence can be considered to be acquired at the same time point; and multiple complex signal sequences in a complex signal sequence group are multiple. obtained at the respective corresponding time points in the time points.

S4. Construct the structural image of the living tissue, the elasticity image of the living tissue, and the blood flow image of the living tissue according to the first complex signal sequence group and/or the second complex signal sequence group corresponding to all the detection positions Various image combinations.

In an embodiment of the present invention, the present invention constructs the structural image of the living tissue, the elasticity image of the living tissue, and the Multiple image combinations in blood flow images of living tissue, including:

According to the first complex signal sequence group corresponding to the first predetermined period of time before the radiation force acts, and/or the second complex signal sequence group corresponding to the second predetermined period after the radiation force acts, construct the said A plurality of images are combined in a structural image of the living body tissue, an elasticity image of the living body tissue, and a blood flow image of the living body tissue.

It can be understood that the technical solution provided by the present invention can intercept the complex signal sequence of a period before the action of the acoustic radiation force and the complex signal sequence of a period of time after the action of the acoustic radiation force for analysis, so as to achieve the purpose of constructing a corresponding image of the living tissue. That is, the multiple time points at which the present invention collects data for all detection positions are fixed time points. Wherein, the time points corresponding to the first complex signal sequence group are all within the first predetermined time period, and the time points corresponding to the second complex signal sequence group are all within the second predetermined time period. Specifically, at the same detection position, the first complex signal sequence that changes with depth at least two time points before the action of the acoustic radiation force can be acquired, and the first complex signal sequence that changes with the depth at least two time points after the action of the acoustic radiation force is obtained. The two complex signal sequences can further analyze the blood flow and/or vibration of the living tissue by analyzing the changes of the complex signal sequences at different time points according to the obtained multiple sets of complex signal sequences at different time points.

In an embodiment of the present invention, the present invention can construct a structural image of living tissue at any point in time, and can also construct structural images of living tissue at different time points. Wherein, the specific method of constructing the structural image of living tissue in the present invention includes: constructing the first complex signal sequence corresponding to all detection positions at the same time point, or according to the second complex signal sequence corresponding to all detection positions at the same time Structural images of living tissue at the same time point.

And/or, according to the corresponding first complex signal sequence of all detection positions at different time points, or according to the corresponding second complex signal sequence of all detection positions at different time points, the structural image of the living tissue at different time points is constructed.

It can be understood that, in the embodiment of the present invention, according to the complex signal sequence (the first complex signal sequence or the second complex signal sequence) of the detection position that changes with depth at any time point, the subsequent detection of the detection position at any time point can be determined. Deeply changed structured data. Furthermore, the structural image of the living tissue at the same time point can be constructed according to the corresponding depth-dependent structural data of all the detection positions at the same time point. Alternatively, structural images of the living tissue at different time points can be constructed according to the corresponding structural data of all detection positions that change with depth at different time points.

The embodiment of the present invention specifically provides a method for determining the structural data corresponding to the detection position, that is, according to any complex signal sequence in the first complex signal sequence and the second complex signal sequence corresponding to the detection position, determine the detection position at any point in time Structural data that varies with depth includes:

According to the detection position changing the amplitude of the complex signal in the complex signal sequence with the depth at any time point, the structure data of the detection position changing with the depth at any time point is determined, wherein the structure data corresponding to all the detection positions is constructed according to the structure data. Structural image of living tissue.

In an embodiment of the present invention, the present invention provides a method for constructing a blood flow image, that is, according to the first complex signal sequence corresponding to the same detection position at different time points, it is determined that the detection position changes with depth at different time points and according to the blood flow data of all detection positions changing with depth at different time points, construct the blood flow images of the living tissue at different time points.

It can be understood that the embodiment of the present invention can determine the blood flow data at any time point of the detection position that changes with the depth according to the first complex signal sequence that changes with the depth position at any time point of the detection position. Furthermore, the blood flow images of the living tissue at different time points are constructed according to the corresponding blood flow data at different time points of all detection positions that change with depth.

The embodiment of the present invention specifically provides a method for determining blood flow data corresponding to a detection position, that is, according to a first complex signal sequence corresponding to the detection position, to determine the blood flow data of the detection position that changes with depth at any point in time, including:

According to the amplitude and/or phase of the complex signals in the first complex signal sequence at the detection position at any time point, the blood flow data of the detection position changing with the depth at any time point is determined.

In an embodiment of the present invention, the present invention provides a method for constructing an elastic image, that is, according to the second complex signal sequence corresponding to the same detection position at different time points, determine the variation of the detection position with the depth at different time points. Vibration data; and determine the vibration distribution images of the living body tissue at different time points according to the vibration data of all detection positions that change with depth at different time points; and construct the vibration distribution images of the living body tissue at different time points. Elastic images of living tissue.

It can be understood that the embodiment of the present invention can determine the vibration data of the detection position at any time point according to the second complex signal sequence that changes with the depth position at any time point of the detection position. Further, according to the corresponding vibration data of all detection positions that change with depth at different time points, the vibration distribution images of the living tissue at different time points are determined, and finally the elasticity image of the living tissue is constructed according to the vibration distribution images.

The embodiment of the present invention specifically provides a method for determining vibration data corresponding to a detection position, that is, according to a second complex signal sequence corresponding to the detection position, to determine the vibration data of the detection position that changes with depth at any point in time, including:

According to the amplitude and/or phase of the complex signals in the second complex signal sequence of the detection position at any time point, the vibration data of the detection position changing with depth at any time point is determined.

And the embodiment of the present invention specifically provides a method for constructing an elasticity image according to a vibration distribution image, that is, constructing an elasticity image of the living tissue according to the vibration distribution images of the living tissue at different time points, including:

According to the vibration distribution images of the living tissue at different time points, the elastic data of the living tissue is calculated, and the elastic data includes at least one of the maximum amplitude, resonance frequency and elastic wave velocity of the living tissue at different spatial positions ;

An elasticity image of the living tissue is constructed from the elasticity data.

In any of the above embodiments of the present invention, the living tissue provided by the present invention is fundus tissue (fundus tissue includes retina, choroid, sclera, etc.), cerebral cortex tissue and skin tissue, which is not specifically limited by the present invention.

Referring to FIG. 2, it is a schematic structural diagram of an optical coherence tomography multimodal imaging device for living tissue provided by an embodiment of the present invention, wherein the optical coherence tomography multimodal imaging device includes: an optical coherence tomography imaging unit 100 and the acoustic radiation force excitation unit 200.

The acoustic radiation force excitation unit 100 is used for generating a fixed receiving position where the acoustic radiation force acts on the living tissue 300 .

The optical coherence tomography unit 200 is used to divide weakly coherent beams of different wavelengths in a predetermined band into a reference beam and a probe beam before the acoustic radiation force acts on the fixed receiving position of the living tissue, and controls the probe beam to irradiate all the probe beams. The detection position of the surface of the living tissue generates a feedback beam, the reference beam is controlled to be irradiated to the mirror to generate a reflected beam, and the feedback beam and the reflected beam are controlled to interfere to generate an interference beam, and the corresponding wavelength of the interference beam is extracted. and performing Fourier transform to obtain the first complex signal sequence whose detection position changes with depth, so as to obtain the first complex signal sequence including multiple first complex signal sequences correspondingly changing with depth at multiple time points and after the acoustic radiation force acts on the fixed receiving position of the living tissue, obtain a set of second complex signals corresponding to depths at multiple time points after the acoustic radiation force acts on the detection position according to the above method The second complex sequence group of the sequence; the above process is repeated until the scanning of all the detection positions of the detection beam on the surface of the living tissue is completed, and all the detection positions of the living tissue before the action of the acoustic radiation force are obtained. a complex signal sequence group and all second complex signal sequence groups after the action; according to the first complex signal sequence group and/or and the second complex signal sequence group corresponding to all detection positions, construct the structural image of the living tissue, all the A plurality of images are combined in the elasticity image of the living tissue and the blood flow image of the living tissue.

Specifically, the device and method provided by the embodiments of the present invention realize dual-modal imaging of blood flow image and elasticity image, or multi-modal imaging such as tri-modal imaging of structural image, elasticity image and blood flow image, and provide more tissue Structural and functional information, and more conducive to the diagnosis of diseases.

In an embodiment of the present invention, the optical coherence tomography multimodal imaging device provided by the embodiment of the present invention may be a swept-frequency OCT imaging structure. Referring to FIG. 3 , it is a schematic structural diagram of another optical coherence tomography multimodal imaging device for living tissue provided by an embodiment of the present invention, wherein the optical coherence tomography imaging unit 100 provided by the embodiment of the present invention includes: : swept frequency light source 101 , first fiber coupler 102 , first fiber circulator 103 , second fiber circulator 113 , second fiber coupler 104 , first mirror 105 , photodetector 106 and host computer 107 . The first fiber coupler 102 provided in the embodiment of the present invention may be a fiber coupler with a split ratio of 99/1, 90/10, or 80/20, and the second fiber coupler may be a fiber coupler with a split ratio of 50/50 .

The swept-frequency light source 101 is used to output the swept-frequency weakly coherent laser light as weakly coherent light beams with different wavelengths within a predetermined wavelength band.

The first fiber coupler 102 is used for splitting the swept-frequency weakly coherent laser light into the reference beam and the probe beam.

the first fiber circulator 103 is used for transmitting the reference beam to the first mirror 105, and transmitting the reflected beam reflected by the first mirror 105 to the second fiber coupler 104; and The second fiber circulator 113 is used to transmit the probe beam to the probe position on the surface of the living tissue 300 to generate a feedback beam, and transmit the feedback beam to the second fiber coupler 104 .

The second fiber coupler 104 is used for interfering the reflected light beam and the feedback light beam to generate an interference light beam.

And, the photodetector 106 is used to detect the interference beam and convert it into an electrical signal and then transmit it to the host computer 107 , and the host computer 107 is used to extract the fixed receiving position before the acoustic radiation force acts on the living tissue. The interference signal sequence corresponding to the wavelength in the interference beam is obtained, and the Fourier transform is performed to obtain the first complex signal sequence that the detection position changes with the depth, so as to obtain a plurality of first complex signals including a plurality of time points corresponding to the depth change. A first complex signal sequence group of a complex signal sequence; and after the acoustic radiation force acts on the fixed receiving position of the living tissue, the detection position is obtained in the above-mentioned manner. After the acoustic radiation force acts, it includes a plurality of time points corresponding to depths A second complex sequence group of a plurality of second complex signal sequences that are changed. The above process is repeated until the scanning of all the detection positions of the detection beam on the surface of the living tissue is completed, and all the first complex signal sequence groups and the effects of all the detection positions of the living tissue before the action of the acoustic radiation force are obtained. All second complex signal sequence groups after. Finally, according to the first complex signal sequence group and/or the second complex signal sequence group corresponding to all detection positions, construct the structure image of the living tissue, the elasticity image of the living tissue, and the blood flow image of the living tissue Various image combinations.

Further, in order to improve the performance of the optical coherence tomography multimodal imaging device, as shown in FIG. 3 , the optical coherence tomography imaging unit 100 provided in the embodiment of the present invention further includes: a first collimating mirror 108 , a first A focusing lens 109 , a second collimating mirror 110 , a first scanning galvanometer 111 and a scanning lens 112 .

The first collimating mirror 108 and the first focusing lens 109 are arranged in the optical path between the first optical fiber circulator 103 and the first reflecting mirror 105, and the first focusing lens 109 is arranged at the The optical path between the first collimating mirror 108 and the first reflecting mirror 105 is defined.

And, the second collimating mirror 110, the first scanning galvanometer 111 and the scanning lens 112 are arranged in the optical path between the second optical fiber circulator 113 and the living tissue 300, and the first A scanning galvanometer 111 is arranged on the optical path between the second collimating mirror 110 and the scanning lens 112 , and the scanning lens 112 is arranged between the first scanning galvanizing mirror 111 and the living tissue 300 . light path.

It can be understood that, in the swept-frequency OCT imaging structure provided by the embodiment of the present invention, the swept-frequency weakly coherent laser output by the swept-frequency light source is split into the reference beam and the probe beam by the first fiber coupler, and the reference beam enters the reference branch, while the The probe beam enters the tissue branch. The reference beam passes through the first optical fiber circulator, the first collimating mirror and the first focusing lens and then enters the first reflecting mirror for reflection, and the reflected reflected beam is reversely transmitted to the first optical fiber circulator according to the original optical path. to the second fiber optic coupler. After passing through the second optical fiber circulator, the second collimating mirror, the first scanning galvanometer and the scanning lens, the detection beam enters the detection position on the surface of the living tissue to generate a feedback beam, and the feedback beam is reversely transmitted to the second optical fiber according to the entering optical path of the detection beam The circulator is transmitted from the fiber optic circulator to the second fiber optic coupler. The second fiber coupler interferes the reference beam and the feedback beam to generate an interference beam, and the double-balanced amplified photodetector detects and converts it into an electrical signal and transmits it to the host computer. The upper computer processes the first complex signal sequence group before the action of the acoustic radiation force and/or the second complex signal sequence group after the action of the acoustic radiation force, which is obtained by processing the electrical signal, and constructs a structural image, an elastic image and a blood flow image. A variety of image combinations.

In an embodiment of the present invention, the optical coherence tomography multimodal imaging device provided by the embodiment of the present invention may be a spectral domain OCT imaging structure. Referring to FIG. 4 , it is a schematic structural diagram of still another optical coherence tomography multimodal imaging device for living tissue provided by an embodiment of the present invention, wherein the optical coherence tomography imaging unit 100 provided by the embodiment of the present invention includes: : continuous spectrum light source 121 , third fiber coupler 122 , second mirror 123 , grating 124 , camera 125 and host computer 126 . The third fiber coupler provided in the embodiment of the present invention may be a fiber coupler with a split ratio of 90/10 and 80/20.

The continuous spectrum light source 121 is used for outputting continuous spectrum weakly coherent light as weakly coherent light beams with different wavelengths within a predetermined wavelength band.

The third fiber coupler 122 is used for splitting the continuous spectrum weakly coherent beam into the reference beam and the probe beam; the second mirror 123 is used for receiving the reference beam and then reflecting it into a reflected beam, and the detection position of the living tissue receives the detection beam and generates a feedback beam; and the third fiber coupler 122 is used to interfere the reflected beam reflected by the second mirror 123 with the feedback beam Generate interference beams.

And, the grating 124 is used for splitting the interference light beam and then transmitting it to the camera 125, the camera 125 is used for photoelectric conversion and then transmitted to the host computer 126, and the host computer 126 is used for extracting the The acoustic radiation force acts on the interference signal sequence corresponding to the wavelength in the interference beam before the fixed receiving position of the living tissue, and performs Fourier transform to obtain the first complex signal sequence in which the detection position changes with the depth. A first complex signal sequence group of a plurality of first complex signal sequences corresponding to a plurality of first complex signal sequences that change with depth at a plurality of time points; and after the acoustic radiation force acts on the fixed receiving position of the living tissue, obtaining the detection position at the acoustic radiation according to the above method After the force is applied, a second complex sequence group including a plurality of second complex signal sequences corresponding to a plurality of time points that change with depth. The above process is repeated until the scanning of all the detection positions of the detection beam on the surface of the living tissue is completed, and all the first complex signal sequence groups of all the detection positions of the living tissue before the action of the acoustic radiation force and after the action are obtained are obtained. All second complex signal sequence groups of . Finally, according to the first complex signal sequence group and/or the second complex signal sequence group corresponding to all detection positions, construct the structure image of the living tissue, the elasticity image of the living tissue, and the blood flow image of the living tissue Various image combinations.

Further, in order to improve the performance of the optical coherence tomography multimodal imaging device, as shown in FIG. 4 , the optical coherence tomography imaging unit 100 provided in this embodiment of the present invention further includes: a unidirectional light transmission isolator 127 , The third collimating mirror 128, the attenuator 129, the first lens 130, the fourth collimating mirror 131, the second scanning mirror 132, the second lens 133, the fifth collimating mirror 134, the third lens 135 and the fourth lens 136.

The isolator 127 is disposed in the optical path between the continuous spectrum light source 121 and the third fiber coupler 122 .

The third collimating mirror 128 , the attenuator 129 and the first lens 130 are arranged in the optical path between the third fiber coupler 122 and the second reflecting mirror 123 , and the attenuator 129 The optical path between the third collimating mirror 128 and the first lens 130 is disposed, and the first lens 130 is disposed in the optical path between the attenuator 129 and the second reflecting mirror 123 .

The fourth collimating mirror 131 , the second scanning galvanometer 132 and the second lens 133 are arranged in the optical path between the third fiber coupler 122 and the living tissue 300 , and the second The scanning galvanometer 132 is arranged on the optical path between the fourth collimating mirror 131 and the second lens 133 , and the second lens 133 is arranged between the second scanning galvanometer 132 and the living tissue 300 . the light path.

The fifth collimating lens 134 and the third lens 135 are arranged on the optical path between the third fiber coupler 122 and the grating 124, and the third lens 135 is arranged on the fifth collimator The optical path between the mirror 134 and the grating 124 .

And, the fourth lens 136 is disposed on the optical path between the grating 124 and the camera 125 .

It can be understood that in the spectral domain OCT imaging structure provided by the embodiment of the present invention, after the continuous spectrum weakly coherent light output by the continuous spectrum light source passes through the isolator, it is split into a reference beam and a probe beam by a third fiber coupler, wherein the reference beam is into the reference branch, while the probe beam enters the tissue branch. The reference beam enters the second reflector after passing through the third collimating mirror, the attenuator and the first lens, and the reflected reflected beam is reversely transmitted to the third fiber coupler according to the original optical path. After passing through the fourth collimating mirror, the second scanning galvanometer and the second lens, the detection beam enters the living tissue to generate a feedback beam, and the feedback beam is reversely transmitted to the third fiber coupler according to the entering optical path of the detection beam. The third fiber coupler interferes the reflected beam and the feedback beam to generate an interference beam, and the interference beam passes through the fifth collimator and the third lens and then enters the grating for beam splitting, which spatially separates the interference light of different wavelengths; and then passes through the fourth lens Then, photoelectric conversion is performed on the camera, and the host computer processes the first complex signal sequence group before the action of the acoustic radiation force and/or the second complex signal sequence group after the action of the acoustic radiation force, which is obtained by processing the electrical signal. Various image combinations in image, elasticity image and blood flow image.

As shown in FIG. 3 and FIG. 4 , the acoustic radiation force excitation unit 200 provided by the embodiment of the present invention includes: a signal source 210 , an amplifier 220 and an ultrasonic transducer 230 .

The signal source 210 is used to generate high-frequency periodic signals;

The amplifier 220 is used for amplifying the high frequency periodic signal;

And, the ultrasonic transducer 230 is configured to generate the acoustic radiation force and act on the fixed receiving position of the living tissue 300 after receiving the high-frequency periodic signal.

In an embodiment of the present invention, the signal source 210 provided by the present invention includes a waveform generator, and the waveform generator is used to generate the detection signal of a high-frequency sine wave, square wave or triangular wave.

It can be understood that in the acoustic radiation force excitation unit provided by the embodiment of the present invention, the waveform generator generates a high-frequency sine wave, square wave or triangle wave, which is amplified by an amplifier and then drives the ultrasonic transducer to realize remote mechanical excitation of living tissue. For example, when the living tissue is the fundus tissue, the waveform generator generates a high-frequency sine wave, square wave or triangle wave, which is amplified by the amplifier and then drives the ultrasonic transducer to realize the remote mechanical excitation of the fundus tissue. Specifically, the ultrasonic transducer is coupled by ultrasonic waves. The material (water or ultrasonic glue) enters the eyeball and forms an acoustic radiation force field in the fundus, which induces tiny vibrations of the fundus tissue; ultrasound can pass through the cornea, lens and other eye tissues, and directly focus on the fundus to generate acoustic radiation force, which is non-invasive, Non-contact and precise focusing advantages.

包含幅度A_{x，y，z，t}部分和相位

部分。其中(x,y)表示与探测光束垂直平面的坐标，z表示探测光束方向(深度方向)的坐标，如图5所示。图6中，

表示位置(x,y)时间t₁随波长λ改变的干涉信号序列；

表示位置(x,y)时间t₂随波长λ改变的干涉信号序列；

表示位置(x,y)时间t₁随深度z改变的复数信号序列；

表示位置(x,y)时间t₂随深度z改变的复数信号序列。The signal processing process of the technical solution provided by the embodiment of the present invention is described in more detail below. 5 and 6, FIG. 5 is a schematic structural diagram of a probe beam and living tissue provided by an embodiment of the present invention, and FIG. 6 is a schematic diagram of transformation of an interference signal sequence and a complex signal sequence provided by an embodiment of the present invention. Among them, the host computer provided by the embodiment of the present invention collects the interference signal sequence Γ _{x, y, t} (λ) in which a certain lateral position (x, y) changes with the wavelength λ at time t, removes noise by filtering, and then performs The Fourier transform is converted to the frequency domain to obtain a complex signal sequence F _x,y,t (Z) (either the first complex signal sequence or the second complex signal sequence) at position (x,y) and time t as a function of depth z. Therefore, at time t, the complex signal at the spatial position (x, y, z) can be expressed as

Contains magnitude A _{x, y, z, t} parts and phase

part. Where (x, y) represents the coordinates of the plane perpendicular to the probe beam, and z represents the coordinates of the probe beam direction (depth direction), as shown in Figure 5. In Figure 6,

represents the interference signal sequence that the position (x, y) time t ₁ changes with the wavelength λ;

represents the interference signal sequence that the position (x, y) time t ₂ changes with the wavelength λ;

represents the complex signal sequence that the position (x, y) time t ₁ changes with the depth z;

A complex signal sequence representing position (x, y) time t ₂ as a function of depth z.

In this way, after obtaining the amplitude and phase of the complex signal in the complex signal sequence, the structural data can be determined according to the amplitude of the complex signal, the blood flow data can be determined according to the amplitude and/or phase of the complex signal, and the amplitude and/or phase of the complex signal can be determined. Vibration data.

Regarding the structural imaging of living tissue provided by the embodiment of the present invention, referring to FIG. 7 , which is a schematic structural diagram of different scanning modes for structural imaging provided by the embodiment of the present invention, when the structural imaging of living tissue is performed, a complex signal sequence is extracted. The amplitude information of the complex signal is sufficient. A scan can obtain a one-dimensional image along the depth direction, B scan can obtain a two-dimensional cross-sectional image, and C scan can obtain a three-dimensional image.

Regarding the blood flow angiography imaging of living tissue provided by the embodiments of the present invention, the blood flow angiography imaging based on OCT utilizes the light scattering changes caused by the movement of red blood cells in the blood flow to obtain the blood flow information and high-resolution blood flow in the living tissue without labels. web image. Using the amplitude information and/or phase information of the complex signal, the blood flow image is obtained by calculating the difference of the time series signals. In the following analysis, F _t and F _t+1 are used to represent the complex signals at the same three-dimensional spatial position (x, y, z) at time t and time t+1, and blood angiography imaging includes the following imaging methods:

1. Doppler phase analysis

的关系如下所示：The phase change of the complex signal can be used to calculate the vibrational velocity and displacement of light-scattering particles in living tissue. Velocity V of Scattering Particles in Living Tissue and Phase Variation of Complex Signals in Time Interval ΔT

The relationship is as follows:

可以通过复数信号计算，如下所示：Among them, n represents the optical refractive index of living tissue, λ represents the central wavelength of the probe beam in vacuum, θ represents the angle between the particle moving direction and the probe beam, and V×cos(θ) represents the speed of the light scattering particle along the probe beam direction. weight. Phase change

It can be calculated from a complex signal as follows:

Among them, Im represents the calculation of the real part of the complex number, Re represents the calculation of the imaginary part of the complex number, F _t and E _t+1 respectively represent the complex signals at different times (t and t+1) and the same spatial position, t and t+ The time interval of 1 time is ΔT.

2. Doppler intensity variance

I _flow represents the flow velocity, and M represents the number of samplings at the same spatial location.

3. Amplitude decorrelation

4. Doppler Phase Variance

5. Speckle variance

6. Intensity relative standard deviation

7. Intensity subtraction

8. Subtract complex signals

FIG. 8 is a blood flow image and a projection diagram thereof analyzed by the above-mentioned Doppler intensity variance method according to an embodiment of the present invention. Before the acoustic radiation force acts, according to the blood flow data of all detection positions (x, y) changing with the depth z at the same time point, a three-dimensional blood flow image and its projection image of the living tissue at the same time point are constructed.

The elasticity imaging of living tissue provided by the embodiment of the present invention is used to describe the non-permanent deformation property of living tissue under the action of stress. The elastic modulus of living tissue, including Young's modulus, shear modulus, bulk modulus, and compressive modulus, is calculated from the slope of the stress-strain curve during elastic deformation. In biomedical applications, Young's modulus and shear modulus are often measured to evaluate the elastic properties of soft tissue. At the same time, to simplify tissue biomechanical properties, tissue is generally assumed to be a mechanically homogeneous and incompressible material in small areas. The ratio of loading stress and small deformation strain remains constant in a small homogeneous region of incompressible elastic tissue, which is direction-independent in isotropic tissue and direction-dependent in anisotropic tissue.

From vibration measurement of living tissue to estimation of elastic properties, the three methods provided by the embodiments of the present invention include comparison of maximum vibration amplitudes, measurement of resonance frequency, and calculation of elastic wave velocity. When the same pressure is applied to different tissues, the maximum vibration amplitudes can be directly compared to qualitatively evaluate elastic properties, softer tissues will exhibit larger vibration amplitudes. The resonance frequency has an approximate linear relationship with the square root of Young's modulus. By measuring the resonance frequency of the tissue and comparing it with the calibrated curve, the Young's modulus of the tissue can be calculated. The elastic wave propagation speed can also be measured, and the elastic modulus can be calculated based on the quantitative relationship between the wave speed and the elastic modulus. When calculating the elastic properties with these three methods, it is necessary to first use OCT to detect the tiny vibration of the tissue. The three methods are:

1. Comparison of the maximum vibration amplitude

When the vibration amplitude is detected by the Doppler phase analysis OCT method, the applied acoustic radiation force is usually parallel or oblique to the probe beam. Young's modulus E, as an important parameter for the characterization of elastic properties in biomedical applications, is the ratio of stress σ to strain ε, which can be described as:

where F is the applied force, S is the area where the force is applied, Δz is the change in tissue thickness along the direction of force application, and _z0 is the original thickness of the tissue along the direction of force application. When the external force is uniform within a certain range, the force F/S per unit area on the tissue is roughly the same. Due to the small displacement of the object caused by the external force, the strain is small enough (Δz/z ₀ less than 0.1%), it can be considered that z ₀ remains unchanged during vibration, and thus, the relative Young's modulus can be estimated with Δz approximation.

To calculate Δz, the OCT method can measure the vibration velocity V _t within the time interval ΔT as follows:

Then, the vibration amplitude Δz parallel to the probe beam direction from time t ₁ to t ₂ can be determined by the following equation:

From the vibration amplitude Δz, the difference in relative Young's modulus can be evaluated, the larger the Δz, the smaller the Young's modulus.

2. Resonance frequency detection

Soft tissue as an elastic material can be modeled by elastic springs when the viscosity is ignored and the deformation is relatively small (Δz/z ₀ less than 0.1%). The applied force F is proportional to Δz×k, where Δz is the displacement from the original position and k is the elastic constant. Young's modulus E can also be described by the following equation:

where f is the resonant frequency of the tissue, M is the mass of the tissue, _z0 is the original thickness of the tissue along the force acting direction, and S is the area where the force is applied. Therefore, the resonant frequency f of the tissue is linearly related to the square root of Young's modulus E and can be used to quantify Young's modulus. In order to measure the resonance frequency of the tissue, the frequency of the external force can be modulated, and the amplitude of the tissue can be measured when the frequency of the external force is different. The external force frequency corresponding to the maximum amplitude of the tissue is the resonance frequency of the tissue, that is, the characteristic frequency of the tissue.

3. Elastic wave velocity calculation

When an external force excites tissue at a location, elastic waves can be generated that propagate from the excitation location into the tissue or near the surface. Using OCT to image the propagation of elastic waves, and to measure the wave velocity, the elastic properties of the tissue can be calculated. Elastic waves propagating inside thick tissue are called body waves, including compression and shear waves. Elastic waves that travel close to the surface at a depth of about one wavelength are surface Rayleigh waves.

Shear waves are most commonly used in elastic measurements. Shear waves are shear waves that propagate in a direction perpendicular to the direction of the applied force (ie, the direction of vibration). After excitation by an external force, shear waves exist inside the tissue. Shear modulus is calculated by using:

where ρ is the density of the tissue and _Vs is the velocity of the shear wave. Based on the relationship between shear modulus μ and Young’s modulus E, that is, E=2μ(1+v), the Young’s modulus of a homogeneous isotropic structure can be determined by the following formula:

where v is the Poisson's ratio of the sample. For biological tissues, the Poisson's ratio is about 0.5, since they can be considered as incompressible materials at small strains, and the Young's modulus, E, is equal to 3ρ×V _s ² .

Compression waves are longitudinal waves propagating in the direction of force (ie, the direction of vibration) in a compressible medium. The velocity V _c of the compression wave in a homogeneous isotropic tissue is related to the bulk modulus K, the shear modulus μ and the tissue density ρ, which can be determined by the following formula:

Due to the high-speed propagation of compressional waves and the relatively low sampling rate of current OCT systems, the velocity of compressional waves is difficult to measure by OCT systems.

Surface Rayleigh waves propagate near the tissue surface. Rayleigh waves can be detected at a depth of about one wavelength. When the excitation position of the external force is close to the tissue surface, the detected elastic waves propagating along the tissue surface should be regarded as Rayleigh waves. For a homogeneous isotropic structure, the Young's modulus E can be calculated based on the _Rayleigh wave velocity VR as follows:

where v is the Poisson's ratio and ρ is the density of the sample.

FIG. 9 is a schematic diagram of acquisition of four-dimensional (x, y, z, t) signals and construction of a vibration image after an acoustic radiation force acts according to an embodiment of the present invention. After generating the acoustic radiation force and acting on the fixed receiving position of the living tissue, obtain the second complex signal sequence of the detection position (x ₁ , y ₁ ) at different time points t changing with the depth z after the acoustic radiation force acts; then move The OCT detection position reaches (x ₂ , y ₁ ), and the acoustic radiation force is generated again to act on the fixed receiving position of the living tissue, and the variation of the detection position (x ₂ , y ₁ ) at different time points t after the action of the acoustic radiation force is obtained. The second complex signal sequence with the depth z changing; repeat the above steps, after completing the data acquisition of the detection positions (x ₃ , y ₁ ) and (x ₄ , y ₁ ), change the y coordinate to obtain (x ₁ , y ₂ ), (x ₂ , y ₂ ), (x ₃ , y ₂ ) and (x ₄ , y ₂ ) data, thus completing the acquisition of four-dimensional (x, y, z, t) data after the action of the acoustic radiation force, and constructing the time t Change the space (x,y,z) to vibrate the image.

The invention provides an optical coherence tomography multimodal imaging device and method for living tissue,

Including steps: S1. Divide weakly coherent light beams with different wavelengths in a predetermined band into a reference beam and a probe beam, control the probe beam to irradiate the detection position on the surface of the living tissue to generate a feedback beam, and control the reference beam to illuminate the mirror. Generate a reflected beam, and control the feedback beam and the reflected beam to interfere to generate an interference beam, extract a corresponding interference signal sequence in the interference beam that changes with the wavelength, and perform Fourier transform to obtain the first detection position that changes with the depth. A complex signal sequence, thereby obtaining a first complex signal sequence group including a plurality of first complex signal sequences corresponding to a plurality of time points that change with depth; S2, generating an acoustic radiation force acting on a fixed receiving position of the living tissue, and After the sound radiation force acts on the detection position obtained in the manner of step S1, it includes a second complex number sequence group of a plurality of second complex number signal sequences correspondingly changing with depth at multiple time points; S3, repeating the steps S1 and S2 until the scanning of all the detection positions of the detection beam on the surface of the living tissue is completed, obtain all the first complex signal sequence groups of all detection positions of the living tissue before the action of the acoustic radiation force and all the first complex signal sequence groups after the action A second complex signal sequence group; S4. Construct the structural image of the living tissue, the elasticity image of the living tissue, and the Various image combinations in the blood flow image of living tissue. It can be seen that the optical coherence tomography multimodal imaging method provided by the present invention can construct various image combinations in the structure image, elasticity image and blood flow image of the living tissue, and then can simultaneously measure the corresponding information of the structure, elasticity and blood flow distribution of the living tissue , to improve the accuracy of disease diagnosis in living tissue.

The above description of the disclosed embodiments enables any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. an optical coherence tomography multimodal imaging method of living tissue, is characterized in that, comprises the steps: S1. Divide weakly coherent beams of different wavelengths in a predetermined band into a reference beam and a detection beam, control the detection beam to irradiate the detection position on the surface of the living tissue to generate a feedback beam, and control the reference beam to irradiate the mirror to generate a reflected beam , and control the interference of the feedback beam and the reflected beam to generate an interference beam, extract the corresponding interference signal sequence that changes with the wavelength in the interference beam, and perform Fourier transform to obtain the first complex signal sequence of the detection position that changes with depth , so as to obtain a first complex signal sequence group including a plurality of first complex signal sequences corresponding to a plurality of time points that change with depth; S2. Generate an acoustic radiation force to act on the fixed receiving position of the living tissue, and obtain the detection position according to the method of step S1. After the acoustic radiation force acts, it includes a plurality of second time points corresponding to changes with depth. a second complex sequence group of complex signal sequences; S3. Repeat the steps S1 and S2 until the scanning of all the detection positions of the detection beam on the surface of the living tissue is completed, and obtain all the first complex numbers of all the detection positions of the living tissue before the action of the acoustic radiation force a set of signal sequences and all second complex signal sequence sets after action; S4. Construct the structural image of the living tissue, the elasticity image of the living tissue, and the blood flow image of the living tissue according to the first complex signal sequence group and/or the second complex signal sequence group corresponding to all the detection positions Various image combinations. 2. The optical coherence tomography multimodal imaging method of living tissue according to claim 1, characterized in that, according to the first complex signal sequence group and/or the second complex signal sequence group corresponding to all detection positions, construct the Multiple image combinations in the structural image of the living tissue, the elasticity image of the living tissue, and the blood flow image of the living tissue, including: According to the first complex signal sequence group corresponding to the first predetermined period of time before the radiation force acts, and/or the second complex signal sequence group corresponding to the second predetermined period after the radiation force acts, construct the said A plurality of images are combined in a structural image of the living body tissue, an elasticity image of the living body tissue, and a blood flow image of the living body tissue. 3. The optical coherence tomography multimodal imaging method of living tissue according to claim 1, characterized in that, according to the first complex signal sequence corresponding to all detection positions at the same time point, or according to all detection positions at the same time point the corresponding second complex signal sequence to construct a structural image of the living tissue at the same time point; And/or, according to the corresponding first complex signal sequence of all detection positions at different time points, or according to the corresponding second complex signal sequence of all detection positions at different time points, the structural image of the living tissue at different time points is constructed. 4. The optical coherence tomography multimodal imaging method of living tissue according to claim 3, characterized in that, according to any one complex signal sequence in the first complex signal sequence and the second complex signal sequence corresponding to the detection position, determine The structural data of the detection position changing with depth at any point in time includes: According to the detection position changing the amplitude of the complex signal in the complex signal sequence with the depth at any time point, the structure data of the detection position changing with the depth at any time point is determined, wherein the structure data corresponding to all the detection positions is constructed according to the structure data. Structural image of living tissue. 5 . The optical coherence tomography multimodal imaging method of living tissue according to claim 1 , wherein, according to the first complex signal sequences corresponding to the same detection position at different time points, it is determined that the detection position is at different times. 6 . The blood flow data of the point changing with the depth; and constructing the blood flow image of the living tissue at different time points according to the blood flow data of all detection positions changing with the depth at different time points. 6 . The optical coherence tomography multimodal imaging method of living tissue according to claim 5 , wherein, according to the first complex signal sequence corresponding to the detection position, it is determined that the detection position changes with depth at any point in time. 7 . blood flow data, including: According to the amplitude and/or phase of the complex signals in the first complex signal sequence at the detection position at any time point, the blood flow data of the detection position changing with the depth at any time point is determined. 7 . The optical coherence tomography multimodal imaging method of living tissue according to claim 1 , wherein, according to the second complex signal sequences corresponding to the same detection position at different time points, it is determined that the detection position is at different times. 8 . Vibration data of points changing with depth; and according to the vibration data of all detection positions changing with depth at different time points, determine the vibration distribution images of the living body tissue at different time points; and according to the vibration data of the living body tissue at different time points The distribution image is used to construct an elastic image of the living tissue. 8 . The optical coherence tomography multimodal imaging method of living tissue according to claim 7 , wherein, according to the second complex signal sequence corresponding to the detection position, it is determined that the detection position changes with depth at any point in time. 9 . vibration data, including: According to the amplitude and/or phase of the complex signals in the second complex signal sequence of the detection position at any time point, the vibration data of the detection position changing with depth at any time point is determined. 9 . The optical coherence tomography multimodal imaging method of living tissue according to claim 7 , wherein the elastic image of the living tissue is constructed according to the vibration distribution images of the living tissue at different time points, comprising: 10 . : According to the vibration distribution images of the living tissue at different time points, the elastic data of the living tissue is calculated, and the elastic data includes at least one of the maximum amplitude, resonance frequency and elastic wave velocity of the living tissue at different spatial positions ; An elasticity image of the living tissue is constructed from the elasticity data. 10. An optical coherence tomography multimodal imaging device for living tissue, comprising: an optical coherence tomography imaging unit and an acoustic radiation force excitation unit; The acoustic radiation force excitation unit is used to generate a fixed receiving position where the acoustic radiation force acts on the living tissue; The optical coherence tomography unit is used to divide weakly coherent beams of different wavelengths in a predetermined band into a reference beam and a probe beam before the acoustic radiation force acts on the fixed receiving position of the living tissue, and controls the probe beam to irradiate the probe beam to the The detection position on the surface of the living tissue generates a feedback beam, the reference beam is controlled to be irradiated to the mirror to generate a reflected beam, and the feedback beam and the reflected beam are controlled to interfere to generate an interference beam, and the corresponding wavelength-changing beam in the interference beam is extracted. Interfering with the signal sequence, and performing Fourier transform to obtain the first complex signal sequence in which the detection position changes with depth, so as to obtain a first complex signal sequence group including a plurality of first complex signal sequences corresponding to a plurality of time points that change with depth ; and after the acoustic radiation force acts on the fixed receiving position of the living tissue, obtain a set of detection positions in the above-mentioned manner. After the acoustic radiation force acts, a plurality of second complex signal sequences corresponding to a plurality of time points that change with depth are obtained. The second complex sequence group of The complex signal sequence group and all the second complex signal sequence groups after the action; according to the first complex signal sequence group and/or and the second complex signal sequence group corresponding to all detection positions, construct the structural image of the living tissue, the A plurality of images are combined in the elasticity image of the living tissue and the blood flow image of the living tissue.

Images